- Neurofibromatosis type II (NF2) is associated with tumors of the nerves, brain, and spinal cord. Most people with NF2 develop vestibular schwannomas, or tumors on the hearing and balance nerves. As they grow, vestibular schwannomas can cause hearing loss and balance problems. If they grow very large they can cause more serious problems, such as seizures, loss of eyesight, weakness, speech problems, and problems with the sense of touch. More research is needed into NF2 because researchers do not completely understand why these tumors occur or what makes them grow over time.